What is a good way to label a multi-purpose PIN?

Many SoCs have multi purpose PINs,
Is there some way to label them in a good manner ?

There are two cases:

  1. I want to route these pins to board connection PINs, and I don’t know what it will be as a function.
  2. I want to use build a hierachical sheet for the SoC as reusable module.

Craftyjon answered my with Alternate Pin Definitions

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I am selecting the functions I expect I will use and list them all (skipping those I don’t expect to use) in as short as possible form.
I2C1_SDA will be in my list simply Sda or Sda0 if there are more than one I2C that can be connected to the port this pin is a part of.

Yeah, if you are meaning it as label, not Pin definition.

I was answering the question on labeling them.
I have never used Alternate pin definitions - I even didn’t know they exists.
I will think if to use it or not in future, but one day is too short to have established opinion.
Pro: - you have shorter labels at finished schematic,
Anty: - you don’t see at schematic to what pin you can connect the line you are just connecting.

Thanks. I actually meant label PIN in a symbol definition.
I have started to use Alternate Pin Definition in my current design

Only really useful if you use the ERC, which I believe you do not. :slightly_smiling_face:

Yes. I never run ERC (but always DRC).
I didn’t checked it but I suppose that after placing symbol at schematic you are able to select from alternate definitions of each pin. It can be a method of showing at schematic what pin function is intended to be used. I design schematic and PCB and when (after month or two) PCBs come assembled my brother writes the software for them. He never needed such information from me, but the schematic can be more clear. Worth considering…
Writing this post I got the idea that one of alternate can contain all pin functions and it should be used during schematic drawing when I can move a wire (practically a net label) from one pin to the other to help me see what is possible. And then when PCB is finished so no next wire swaps are expected I could select for each pin what its function was (at the end) selected.
But if I will start then to do the next PCB reversion I will have to begin from changing all pins back to the full lists. Seems more complications than benefits.

No, this needs to be done in the symbol editor.

I too do not bother with ERC. As someone very knowledgeable has just stated:

:grin: :grin: :grin:

This changes everything (I have V7 at work, now I am at home at PC with Win7 so I have no V7 here so I didn’t checked anything an base only on what I see written).
When you have to select it in symbol editor than it will easily propagate to all other schematics (after modifying any symbol I run update at schematic and always select to update all to have everything consistent with my libraries).
Now I don’t see any use of it for me.

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